It is known in the art to use a set of shaped "fingers"or pick-up elements mounted on a stationary component and adapted to ride in the grooves of a rotary element disposed within the housing of a rotary component. An example of a typical prior art design of pick-up element for slip rings or rotary connectors is shown in FIG. 1. The rotary element 100 is mounted to shaft 110 and disposed within a housing 120 and has a plurality of wires 130 connected to respective conductive grooves 140 of the rotary element 100. Parts 100 to 140 constitute the rotary component of the slip ring or rotary connector.
A connector 150 terminates a further plurality of wires 160 which are individually soldered to a wiring block 170. A plurality of pick-up fingers 180 are manually attached to the fixed element or wiring block 170 via epoxy and are bent to provide a kink or coined area for proper pressure. The pick-up fingers 180 may be fabricated from a gold alloy or any good conductive metal selected for maximum wear and conductivity. Parts 150 to 180 constitute the fixed or stationary component of the slip ring or rotary connector and are dimensioned so as to fit into a slot 190 of the housing 120 which contains the wired rotary element.
In operation, the fingers or pick-up elements 180 ride in the grooves 140 of the rotary element 100 to transform an electrical signal on the wires 160 to the rotary component. As will be appreciated from the drawing of FIG. 1, the stationary and rotary components cannot be "hard-wired" as the wires 160 would twist and break.
Prior art designs such as exemplified by FIG. 1, have been in existence for a long period of time and have been refined to the point where extremely long life (i.e. number of revolutions) has been achieved using the components such as set forth in FIG. 1. Many factors influence the durability and lifetime of such rotary connectors, including the materials used, forces of one component against another, surface finishes of the contacting elements 140 and 180, the amount of current flowing (i.e. amperage) and conductivity of the materials used.
It will be appreciated that manual attachment of the pick-up fingers 180 to the wiring block 170 followed by manual bending to provide proper pressure against the conductive grooves 140 and careful manual fitting of the parts into housing 120 is extremely labor intensive and therefore adds cost to the finished product.